[Mesa-dev] [PATCH 3/3] glsl/linker: validate explicit locations for SSO programs

[Iago Toral Quiroga]

---
 src/compiler/glsl/link_varyings.cpp | 53 +++++++++++++++++++++++++++++++++++++
 src/compiler/glsl/link_varyings.h   |  4 +++
 src/compiler/glsl/linker.cpp        |  6 +++++
 3 files changed, 63 insertions(+)

diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp
index dffb4f98df..d7e407184d 100644
--- a/src/compiler/glsl/link_varyings.cpp
+++ b/src/compiler/glsl/link_varyings.cpp
@@ -599,6 +599,59 @@ validate_explicit_variable_location(struct gl_context *ctx,
 }
 
 /**
+ * Validate explicit locations for SSO programs. For non-SSO programs this
+ * is alreadty done in cross_validate_outputs_to_inputs().
+ */
+void
+validate_sso_explicit_locations(struct gl_context *ctx,
+                                struct gl_shader_program *prog)
+{
+   assert(prog->SeparateShader);
+   struct explicit_location_info explicit_locations_in[MAX_VARYINGS_INCL_PATCH][4];
+   struct explicit_location_info explicit_locations_out[MAX_VARYINGS_INCL_PATCH][4];
+
+   for (unsigned i = 0; i <= MESA_SHADER_FRAGMENT; i++) {
+      if (prog->_LinkedShaders[i] == NULL)
+         continue;
+
+      gl_linked_shader *sh = prog->_LinkedShaders[i];
+
+      memset(explicit_locations_in, 0, sizeof(explicit_locations_in));
+      memset(explicit_locations_out, 0, sizeof(explicit_locations_out));
+
+      foreach_in_list(ir_instruction, node, sh->ir) {
+         ir_variable *const var = node->as_variable();
+
+         if (var == NULL ||
+             !var->data.explicit_location ||
+             var->data.location < VARYING_SLOT_VAR0 ||
+             (var->data.mode != ir_var_shader_in &&
+              var->data.mode != ir_var_shader_out))
+            continue;
+
+         /* Vertex shader inputs and fragment shader outputs are validated
+          * in assign_attribute_or_color_locations, skip them.
+          */
+         if (sh->Stage == MESA_SHADER_FRAGMENT &&
+             var->data.mode == ir_var_shader_out)
+            continue;
+
+         if (sh->Stage == MESA_SHADER_VERTEX &&
+             var->data.mode == ir_var_shader_in)
+            continue;
+
+         if (!validate_explicit_variable_location(
+               ctx,
+               var->data.mode == ir_var_shader_in ? explicit_locations_in :
+                                                    explicit_locations_out,
+               var, prog, sh)) {
+            return;
+         }
+      }
+   }
+}
+
+/**
  * Validate that outputs from one stage match inputs of another
  */
 void
diff --git a/src/compiler/glsl/link_varyings.h b/src/compiler/glsl/link_varyings.h
index 081b04ea38..e8486208a2 100644
--- a/src/compiler/glsl/link_varyings.h
+++ b/src/compiler/glsl/link_varyings.h
@@ -300,6 +300,10 @@ link_varyings(struct gl_shader_program *prog, unsigned first, unsigned last,
               struct gl_context *ctx, void *mem_ctx);
 
 void
+validate_sso_explicit_locations(struct gl_context *ctx,
+                                struct gl_shader_program *prog);
+
+void
 cross_validate_outputs_to_inputs(struct gl_context *ctx,
                                  struct gl_shader_program *prog,
                                  gl_linked_shader *producer,
diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp
index 3798309678..cba14f940b 100644
--- a/src/compiler/glsl/linker.cpp
+++ b/src/compiler/glsl/linker.cpp
@@ -4938,6 +4938,12 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
       prev = i;
    }
 
+   /* Validate location aliasing for SSO programs (this is done during
+    * cross_validate_outputs_to_inputs for non-SSO programs).
+    */
+   if (prog->SeparateShader)
+      validate_sso_explicit_locations(ctx, prog);
+
    /* Cross-validate uniform blocks between shader stages */
    validate_interstage_uniform_blocks(prog, prog->_LinkedShaders);
    if (!prog->data->LinkStatus)
-- 
2.11.0